Vivitrol is an injectable form of Naltrexone and designed to block the brain's opioid receptors. Essentially, the monthly shot is designed to prevent an opioid user from getting high.

However, experts warn counseling must come along with the medication. Eligible inmates receive a shot of Vivitrol before their release, with counseling and services set up to try and ensure success once back in the community.

According to the Arizona Department of Corrections, 13 eligible inmates enrolled in the program since August, with just two making it to their third shot after leaving prison.

In Maricopa County, nine eligible county inmates have opted for Vivitrol. Of those nine, county officials only know of three who continued seeking treatment after leaving jail.

"I can say that I would have hoped for a better success rate," said Dr. Grant Phillips, the Medical Director for Maricopa County Correctional Health Services.

He also noted the number of people who become eligible for the treatment program is intentionally kept low, to ensure they are providing proper education and services, such as counseling, for when the inmate leaves jail.

Essentially, it's a small sample size, but Vivitrol will continue as an option as a part of their larger substance abuse program.

"The drug itself is effective when used in combination with counseling and strong social support," Phillips said. "Let's face it, someone leaving jail is lacking in a lot of those things."

Phillips says while only nine patients have opted for Vivitrol, they have more than 100 methadone patients just in 2018.

"There may be a lack of interest," Phillips said, noting inmates in the substance abuse program regularly discuss various treatment methods. "Some will have had good experiences, some will not have good experiences, they'll talk about it and they'll kind of share these ideas."

The goal is to help inmates better their lives while reducing the rate at which offenders wind up back behind bars.

Vivitrol programs take many different shapes across the country. For example, in Madison County, Indiana, Vivitrol is sometimes tied to a condition of probation.

The Chief Probation Officer there said roughly 55 percent of participants either successfully completed, or are still a part of, their Vivitrol program. They count that as a success.

Perhaps it's too early to evaluate the programs here in Arizona.

"The anecdotal success is a reason to be optimistic about it," Phillips said. "Offering choice of all the options that are out there and realizing that Vivitrol is going to work for some individuals, we want to make sure it is available to them."

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